Defense expert backs accused former Plymouth officer

Testimony in the federal trial of Shawn Coughlin ended Tuesday with a defense expert saying videotapes of the former Plymouth police sergeant's altercation with a handcuffed prisoner showed nothing that would make him conclude that Coughlin used excessive or unreasonable force.

BOSTON – Testimony in the federal trial of Shawn Coughlin ended Tuesday with a defense expert offering analysis of the former Plymouth police sergeant's videotaped altercation with a handcuffed prisoner.

Charles DiChiara, a veteran Waltham police officer who trains police instructors, told jurors he saw nothing in the video to make him conclude that Coughlin used excessive or unreasonable force.

DiChiara said the video shows numerous incidents in which the prisoner, John Leighton Jr., could be actively resisting or even assaulting Coughlin.

DiChiara, one of only eight instructor trainers in the state, was the last of four witnesses to testify for the defense.

Closing arguments and jury deliberations were expected to begin today after jury instructions from U.S. District Court Judge Nathaniel Gorton.

Coughlin, 47, is accused of violating Leighton's constitutional protection against police use of excessive force after the West Plymouth man's drunken-driving arrest on Nov. 19, 2011. Coughlin is also charged with lying about the incident in a police report.

The case centers on the videotape, which shows Coughlin and other officers struggling with Leighton in a police holding cell.

An expert for the government testified last week that Coughlin used excessive force, hitting Leighton repeatedly with palm and knee strikes.

DiChiara said the video is inconclusive because it is not possible to judge Coughlin's or Leighton's intent or the amount of force they exerted during the struggle. He said there are at least three instances in the video where Leighton could be aggressive or assaultive.

"It looks like three officers are having a hard time controlling him," DiChiara said.

Under cross examination, DiChiara acknowledged that Coughlin may have hit Leighton, as one fellow officer testified, or that Leighton did not resist, as another officer told jurors.

Earlier Tuesday, Coughlin insisted under his own cross examination that he did not know Leighton was handcuffed and that he only had a second to respond to a perceived threat against a fellow officer when he rushed Leighton.

"I reacted to what I saw and to what I perceived," Coughlin testified. "Officer Yule (the other officer) could have been kicked, stabbed, punched. I don't know."

At the close of testimony, Gorton denied a defense motion for acquittal, rejecting suggestions that the government never proved Leighton suffered an injury.